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21.
In this paper, the baseline variation and displacement vector was analyzed using the calculated results of GPS measurements carried out from 1995 to 1996 in North China. Based on these analytical results, we studied the recent tectonic activity. In general, the regional extension is dominant in the direction of proximately EW, but there is a difference in the SN direction. Extension is significant in the Shanxi fault-depression zone and Bohai region, while compression with strike-slip is characterized along the Yishui-Tancheng segment of the Tanlu fault zone. The baseline shortening zone is distributed along the Baotou-Zhangjiakou-Ninghe areas. It is a boundary zone of regional variation where many differences of crustal horizontal deformation are discovered between the southern part and the northern part of this zone. The baseline shortening zone in NE direction is distributed along the Jianchang-Tangshan-Gucheng area. It is consistent with the Tangshan-Xingtai seismic zone which indicates that tectoni  相似文献   
22.
This is a first foray into the historical start and early years of chemometrics from about 1972 onwards.We have gathered interviews with three originators(Kowalski,Wold and Massart)as well as with aselected group of six other well-known chemometricians who gradually became active in the 1970s(Christie,Clementi,Hopke,Martens,Brown and Deming).The interviews include amongst a host ofsubjective recollections a succinct record of the key historical literature as highlighted by the interviewees'own rankings of‘earliest’and‘best’.A discussion of the most general commonalities in these interviews together with other historicalmaterial is presented in the second part of the paper.  相似文献   
23.
Through theoretical analysis and computer simulation,this short communication comments on theresidual bilinearization(RBL)method and compares it with non-bilinear rank annihilation(NBRA)forthe treatment of second-order calibration with non-bilinear data.It is found that these two methods aremathematically equivalent but have different noise propagation properties.The second-order advantage,namely quantitation in the presence of unknown interferences,can be carried over to non-bilinear dataonly if there exists a net analyte rank(NAR)for the analyte of interest.  相似文献   
24.
GPS揭示的现今地壳运动与地震前兆特征   总被引:2,自引:8,他引:2  
利用“中国地壳运动观测网络”产出的GPS观测资料,采用球坐标系下非连续变形算法对资源进行计算,以此为基础,对我国大陆地块及其边界带运动与形变进行了分析。对GPS基准站的连续观测序列采用小波变换进行分解变换,分析了部分震例,探讨了从GPS连续观测序列提取地震前兆的方法。初步取得两点认识:(1)7级以上的大地震主要发生在走滑运动量大的活动边界,且与高应变率地块有关,这可以作为地震中长期预测判据;(2)GPS基准站连续观测序列中的低频段,地震前6个月或稍长时段有一定的前兆异常出现,这可以作为地震中短期预测判据。  相似文献   
25.
东营凹陷负反转构造样式及其运动学特征   总被引:2,自引:0,他引:2  
中、新生代强烈的负反转作用是东营凹陷构造演化的一个重要特色.为了解负反转构造对东营凹陷中、新生代盆地形成过程中的意义, 以高分辨率三维地震资料解释为基础, 详细刻画了东营凹陷负反转构造几何学样式, 并综合运用计算断层活动速率和负反转率以及编制地层位移-距离曲线等方法, 对东营凹陷负反转断层运动学特征进行了系统的定量研究.结果表明, 东营凹陷J3-K1和Ek-Es4两期盆地的主体均是印支期逆冲断层发生负反转作用所致, 总的负反转率约为3.367~8.3, 其中J3-K1时期负反转率为1.388~3.904;负反转构造最终定型于Es3-Es2时期; 负反转作用在空间上呈现出SW至NE逐渐增强的演变规律.东营凹陷负反转构造的研究对于盆地内部深层油气藏的勘探具有重要的理论意义和实际应用价值.   相似文献   
26.
In order to study the origin of the spatial structure of the Northern Hemisphere Annular Mode (NAM),a linear stochastic model is constructed empirically from the output of a GCM run.Optimal stochastic forcing in terms of the maximum variance contribution,which may be potentially related to the maintenance of the NAM,is investigated.Theoretical analysis on the dominant non-modal response to the stochastic forcing shows that this dominance is jointly decided by the properties of forcing and the non-modal grow...  相似文献   
27.
A total of 34 thunderstorms around Shanghai and Wuhan of China are analyzed in order to determine the relationship between total lightning activity and precipitation particle characteristics.Precipitation particle concentration data are obtained from the 2A12 product of TRMM/TMI(Tropical Rainfall Measuring Mission/TRMM Microwave Image) and lightning activity data are from the TRMM/LIS(Lightning Imaging Sensor) and SAFIR3000(Surveillance et Alerte Founder par Interferometric Radioelectirque).On a spatial ...  相似文献   
28.
In this paper,a study of the principal characteristics of the ground deformation disasters in the city of Tianjin caused by the Tangshan earthquake is based on the results from the recent remeasurements of the geodetic controlling network of Tianjin and from on-site investigations after the earthquake.These results show that only the ground deformation in the Ninghe and Hangu areas near the epicenter reflect directly the co-seismic crustal stress,while the serious ground deformation and the engineering earthquake damages in the urban districts of Tianjin are controlled to a great extent by the local engineering geological structures,showing a kind of secondary disaster.Several suggestions are also proposed in the paper concerning the counter-measures for reducing the earthquake damage in big cities.  相似文献   
29.
本文采用变形模型可区分度量的概念进行监测网的优化设计。在算法上采用计算机模拟逐一更新的计算过程。为了克服常规模拟法需要人工干预的缺点,引进了一些规则,利用计算机的判断和推理过程,达到了自动设计的目的。作为示范例子,文中最后还给出了一个模拟监测网的设计结果。  相似文献   
30.
A time-dependent linear model on the equatorial beta plane is developed in this paper.Its verticalstructure consists of two active layers with equal density and temperature above the thermocline and aquasi-stationary layer with constant density below the thermocline.The results of nurnericat experiments show that the direct influence of heat on the equatorial ocean ismuch smaller than that of wind stress.Nevertheless,through the tropical ocean-atmosphere interaction,the change of wind stress resulting from the thermal forcing may set a determinant effect on the equilibriumand anomalous development of the ocean-almosphere circulation.  相似文献   
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